Counting and measurement of ovarian follicles in ultrasound images is a procedure that is performed for fertility assessment in IVF (in vitro fertilization) treatments. The patient's ovaries are regularly scanned with transvaginal ultrasound. The number of ovarian follicles in the ovaries is counted, and the diameter of each ovarian follicle is measured. In some current systems, the diameter of each ovarian follicle is measured manually. The number and diameter of the follicles is tracked over time to assess treatment progress. A steady increase in the number and/or diameter of the follicles may indicate that the patient is responding well to treatment. Once the number and size of the follicles reach a predetermined threshold, eggs will be aspirated, fertilized and re-implanted (or may be frozen).
FIG. 1 is a schematic drawing that is representative of an ultrasound image in which a plurality of follicles 10 are visible. In an ultrasound image, follicles 10 may look like dark chambers.
Segmentation may represent the process of identifying pixels or voxels representing a given structure in an image or set of image data, which may include separating the pixels or voxels from the rest of the image or set of image data. The identification and/or separation of pixels or voxels representing the structure facilitates further processing of information relating to the structure, for example, measurement of the structure, or rendering the structure in a way that is distinct from other structures in the image or set of image data. In order to separate a structure from the rest of the image or set of image data, it is necessary to know which pixels or voxels correspond to which tissue types (or types of artificial object). The image can then be divided into a part of the image or set of image data that represents the tissue type corresponding to the structure, and a remainder that does not represent the tissue type. If there is more than one structure in the image or set of image data of a given tissue type, further techniques may be used to separate discrete structures. Multiple structures may be segmented in one image or set of image data.